The present invention relates generally to the field of semiconductor devices, and more particularly, to active thermal management of semiconductor devices utilizing thermal electric coolers.
Semiconductor devices, whether digital or analog, comprise a variety of circuit components. Just about all of these components generate heat or thermal energy during operation but have their performance degraded by excessive heat. The heat generated by these components is a function of the performance, which includes frequency, power levels, speed of data transfer and the like, at which the devices are operated. While modifications to devices and components can reduce heat generation, increases in performance generally cause increases in heat generation. Consequently, failure to control or dissipate heat adequately can limit performance, or indeed damage the component or limit its life expectancy.
As time goes on, the demand for performance increases. Therefore, semiconductor devices are increasingly required to operate at faster speeds, transfer more data, have a better signal to noise ratio, fit in a smaller area (scale) and the like. Thus, generation of thermal energy by these devices continues to increase. Further, more components are squeezed into ever smaller die areas further increasing heat generation and concentration, that can also affect performance and life expectancy.
Thermal energy can be controlled, thereby facilitating performance, by employing semiconductor cooling techniques. One common technique for managing heat generated by semiconductor devices is to utilize a heatsink. The heatsink is a thermally conductive device that is operable to draw heat from a semiconductor device and dissipate it in the air. Generally, a solid portion of the heatsink is on or near the semiconductor device and fans or blades are on an opposite edge of the heatsink. The blades facilitate dissipation of thermal energy from the heatsink to ambient air.
Another common technique for managing heat generated by semiconductor devices is to employ a cooling fan with a heatsink. The cooling fan is typically mounted on or near blades of the heatsink and facilitates dissipation by blowing air away from or towards the blades.
Another technique for managing heat generated by semiconductor devices is to employ a solid state cooling device called a thermoelectric cooler (TEC). The thermoelectric cooler relies on the Peltier effect, in which a voltage applied to the junction of two dissimilar metals creates a temperature difference between the two metals. This temperature differential can be used for cooling or heating. Thermoelectric coolers are semiconductor devices in and of themselves. They are fabricated from two elements of semiconductor, primarily Bismuth Telluride. The semiconductor is heavily doped to create an n-type region and a p-type region. The junction between the n-type region and the p-type region is a semiconductor thermocouple. At a cold side of the thermoelectric cooler, thermal energy is absorbed by electrons as they pass from a low energy level in the p-type region to a higher energy level in the n-type region. A power supply provides the energy to move electrons through the system. At a hot side, energy is expelled to a heatsink as electrons move from a high energy level in the n-type region to a lower energy level in the p-type region. Heat absorbed at the cold side is pumped to the hot side at a rate proportional to current passing through the circuit.
The following presents a simplified summary in order to provide a basic understanding of one or more aspects of the invention. This summary is not an extensive overview of the invention, and is neither intended to identify key or critical elements of the invention, nor to delineate the scope thereof. Rather, the primary purpose of the summary is to present some concepts of the invention in a simplified form as a prelude to the more detailed description that is presented later.
The present invention facilitates semiconductor cooling by combining a semiconductor die and a thermoelectric cooler into a single, integrated package or system. The thermoelectric cooler is controllably operated so as to dissipate thermal energy generated by the semiconductor die. Active thermal management of the package is performed by a controller, which monitors temperature(s) of the semiconductor die and increases or adjusts cooling such that desired performance levels can be obtained.
The present invention facilitates semiconductor device operation by actively maintaining device temperatures according to desired performance levels. The invention integrates a semiconductor die, a thermoelectric cooler, and active thermal management into a single package so as to actively manage the die temperature. Because of this integration, cooling of the semiconductor die can be improved as compared with conventional cooling systems. Additionally, this thermal management can maintain temperatures that permit desired performance levels (e.g., a relatively high frequency) of operation. A controller, located internal or external to the package, performs temperature measurement and thermoelectric cooler control. The controller can, in some variations, be located on the semiconductor die. Additionally, the present invention can independently thermally manage one or more regions of a semiconductor die and can independently thermally manage a plurality of semiconductor dies.
To the accomplishment of the foregoing and related ends, the invention comprises the features hereinafter fully described and particularly pointed out in the claims. The following description and the annexed drawings set forth in detail certain illustrative aspects and implementations of the invention. These are indicative, however, of but a few of the various ways in which the principles of the invention may be employed. Other objects, advantages and novel features of the invention will become apparent from the following detailed description of the invention when considered in conjunction with the drawings.